TOPIC: How High

When your placing your speakers is there a formula as to how high up the wall they should be placed? What is minimum number of speakers that could be used to be effective? Let's say that this is for a theatre that seats about 250.

In the old Altec Mag days the rule of thumb was the distance apart was the distance off the floor

Modern requirements are usually based on even coverage down the length of the theatre and at a hight sufficient to beam across the room and not distract those directly underneath
(often 1/2 the theatre width or less)

As for distance THX specifies the front speaker typicaly 3/4 of the way to the screen

Thanks to Gregborr for his faith in us that we know the answer to this one. We generally get the speaker distrubution and heights from the sound equipment supplier. Then we coordinate the locations with the acoustic wall treatments, lighting, etc. It seems to me that in stadium theatres, the speakers are usually about 10 to 11 feet off the floor. The speaker arrays usually go 2/3 to 3/4 of the way to the screen, and the spacing seems to be about 8 to 10 feet apart. This is not scientific at all, as we don't have the technology to lay out the speakers.